Safe to delete android_secure folder?

From what I understand (please correct me if I'm wrong), the android_secure folder is a folder where all the App2SD apps go to. Basically, where all of your moved apps go to.

Now every time, I update a ROM or switch ROMs I have to do complete wipe on my phone. When I use Titanium Backup to restore my apps, I must move them all once again to SD.

The reason I ask that is it safe is because for some strange reason when I took a peek inside of my android_secure folder I saw that there was over 500MB+ of data inside. I also saw many duplicates of the same apps and also old apps that I uninstalled ages ago.

So back to the Topic, is it safe to uninstall the android_secure folder?
Has anybody ever cleaned it out when switching ROMs